
Description
The ecm continuously monitors its own internal memory status, internal circuits, and output signals transmitted to the throttle actuator. This self-check ensures that the ecm is functioning properly. If any malfunction is detected, the ecm sets the appropriate dtc and illuminates the mil.
The ecm memory status is diagnosed by internal mirroring of the main cpu and the sub cpu to detect random access memory (ram) errors. The two cpus also perform continuous mutual monitoring. The ecm illuminates the mil and sets a dtc if: 1) outputs from the two cpus are different or deviate from the standards, 2) the signals sent to the throttle actuator deviate from the standards, 3) a malfunction is found in the throttle actuator supply voltage, and 4) any other ecm malfunction is found.

Monitor strategy

Typical enabling conditions
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Typical malfunction thresholds


Inspection procedure
Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

System voltage
Starter relay circuit highCustomize parameters
Customizing function with intelligent
tester (reference)
Hint:
The following item can be customized.
Notice:
When the customer requests a change in a
function, first make sure that the function can be
customized.
Make a note of the current settings before
customizing.
When tr ...
Replacement
discharge refrigerant from refrigeration system
Start up the engine.
Turn the a/c switch on.
Operate the cooler compressor with an engine
speed of approximately 1,000 rpm for 5 to 6 minutes
to circulate the refrigerant and collect the
compressor oil remaining in each component int ...
Mechanical system tests
Stall speed test
Hint:
This test is to check the overall performance of the
engine and transaxle.
Notice:
Do not perform the stall speed test longer than 5
seconds.
To ensure safety, perform this test in an open and
level area that provides good traction.
The stall speed test sh ...